my add-in express is able to add a "Div" tag after each "P" tag.
inside the "Div" tag i have added a "Table" tag with some rows (TR).
my "Table" tag have no border (border="0"), however, when i click on a button to change the DOM tree, all my "Table" tags has some borders and even some style that (it seems) are defined in the original page.

my question is how can i override these styles and to apply only my styles.

This forum is about developing IE extensions. I'm sorry, we cannot help with general HTML-related questions that do not directly relate to our product. I'd suggest googling for the answer. Thank you for your understanding.

No problem. thanks anyway.
in the mean while i have found the problem.
in fact it isn't related to ie extensions.
i will however post the solution in case someone is facing the same problem.
in fact we have a priority order to apply the style to a tag.
from least weight to the higher weight:
external CSS class ==> color:red
internal style tag ==> color:green
style attribute in any html tag ==> color:blue
!important keyword

so if you have an external css class or an internal style tag and you are using a style attribute in any html tag, it mean's that the blue color will be applied to the html tag.
unless you have the keyword !important in the external css class or the internal style tag, in this case the color red or green will be applied to the html tag.

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